Higgs theorists—including Higgs himself—get Nobel Prize in physics

Confirmation of particle's existence leads to award for work published in 1964.

Last year, after decades of waiting, a handful of theorists had their work confirmed with the announcement that scientists had discovered an elusive particle called the Higgs boson. Now, just over a year later, two of those theoreticians are being awarded the Nobel Prize in physics.

The Higgs boson is a manifestation of the Higgs field, an invisible entity that pervades the Universe. Interactions between the Higgs field and particles help provide particles with mass, with particles that interact more strongly having larger masses. But despite its central role in the function of the Universe, the road to the papers that predicted the existence of the Higgs was bumpy, as was the process of discovering it.

The idea of the Higgs was a consequence of studies on the weak force, which controls the decay of radioactive elements. The weak force only operates at very short distances, which suggests that the particles that mediate it (the W and Z bosons) are likely to be massive. While it was possible to use existing models of physics to explain some of their properties, these predictions had an awkward feature: just like another force-carrying particle, the photon, the resulting W and Z bosons were massless.

Over time, theoreticians managed to craft models that included massive W and Z bosons, but they invariably came with a hitch: a massless partner, which would imply a longer-range force. In 1964, however, a series of papers was published in rapid succession that described a way to get rid of this problematic particle. If a certain symmetry in the models was broken, the massless partner would go away, leaving only a massive one. The first of these papers, by François Englert and Robert Brout, proposed the new model in terms of quantum field theory; the second, by Peter Higgs, noted that a single quantum of the field would be detectable as a particle.

Robert Brout died in 2011, so Englert (currently at the Free University of Brussels) was honored for his contributions, as was Higgs, who is at the University of Edinburgh. The third paper, by Gerald Guralnik, Carl Richard Hagen, and Tom Kibble, was not recognized by this award, possibly due to the prize's stipulation that only three people be recognized. (For the same reason, none of the people who spotted the Higgs at the LHC are recognized; as the Nobel documents point out, each of the two detectors credited with the discovery had a staff of over 3,000 researchers.)

But the third paper provided an independent validation of the general approach, as did a completely independent derivation by students in the Soviet Union. By 1967, Steve Weinberg had extended the Higgs mechanism to account for the mass of electrons and heavier leptons, and in 1971, Gerhard ‘t Hooft and Martinus Veltman figured out how to get rid of a few annoying infinities in some of the equations. By 1983, the W and Z bosons had had their masses determined, providing an experimental validation of some of the predictions made by the theoreticians.

But while the Higgs field managed to get a lot of things in the Standard Model to work properly, we still didn't have experimental validation of one of its predictions: the Higgs particle. Precision measurements of the masses of some of the heavier particles put an upper limit on the Higgs mass at about 150GeV, while experiments with the Large Electron-Positron collider (the LHC's predecessor, built in the same tunnel) eliminated everything under 115GeV. Meanwhile, years of running the Tevatron had produced a weak signal of around 120GeV, one that was just over two standard deviations above background noise.

That was where things stood when the LHC started up. Within a few years of operation, the new collider had generated enough data to detect a five-sigma signal at just above 125GeV, enough to announce discovery. On the day of the announcement, Englert and Higgs were in the audience at CERN. Now, they will have a chance to meet again with a different kind of audience—one with the King of Sweden.

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60 Reader Comments

Really shows why the Nobel Prize is anachronistic compared to how modern science works, in physics and other fields. Its a hugely collaborative process, and trying to single out a few individuals like some sort of pseudo-sports stars is not just inaccurate, but even harmful, imo.

Edit - sheesh, its not that I don't think science and scientists don't deserve more recognition. Its just the Nobels are an incredibly archaic way of recognizing discoveries. If you've worked in a lab, you know the PI is just the tip, supported by the ideas and work of postdocs, grads and even very enterprising undergrads. And then there is Big Science, like all this physics work. All those smart people contributing, the huge public outlay for the colliders, etc.

Just saying, tl;dr - the idea that the greatest discoveries of modern science will never involve more than three people's significant contributions is just not square with reality.

Which result these days only had 3 people contributing to it even as major authors? But that's not the only anachronistic thing here.

He now gets to meet The King of Sweden. A man whose only claim to fame is being born to a particular family and not having managed to screw it up too much. Who outside of Sweden should have a reason to care in this day and age?

Notwithstanding the bs, it's wonderful to have lived in a time of major advances in our understanding of the universe.

He now gets to meet The King of Sweden. A man whose only claim to fame is being born to a particular family and not having managed to screw it up too much. Who outside of Sweden should have a reason to care in this day and age?

I'd rather meet the King of Sweden than the Nigerian Prince that keeps emailing me.

I feel sorry for the LHC team, but it's kind of understandable why the Nobel prize is awarded to individuals and not corporations and research centers. It's purpose is to motivate individuals and reward their excellence.

He now gets to meet The King of Sweden. A man whose only claim to fame is being born to a particular family and not having managed to screw it up too much. Who outside of Sweden should have a reason to care in this day and age?

I'd rather meet the King of Sweden than the Nigerian Prince that keeps emailing me.

i dont know the nigerian prince wants to give me money. whats the king of Sweden done for me lately. Also one of their emails slipped passed Gmails spam detector.

Him getting it this year should come at no surprise. The certainty associated with the data for the Higgs particle crossed the 5-sigma threshold last year. The Nobel Prize going to him now is if anything as immediate as it could get.

Him getting it this year should come at no surprise. The certainty associated with the data for the Higgs particle crossed the 5-sigma threshold last year. The Nobel Prize going to him now is if anything as immediate as it could get.

(btw, we're over 6-sigma certainty of the Higgs Boson now)

The 6-sigma tells us the signal is there and it isn't noise, right? But are we sure now that it's the Higgs Boson? Could it still be another particle or some other phenomenon other than the Higgs? Honest question, I'd love to know and am an absolute layman in physics.

Him getting it this year should come at no surprise. The certainty associated with the data for the Higgs particle crossed the 5-sigma threshold last year. The Nobel Prize going to him now is if anything as immediate as it could get.

The point is the time between when Higgs et. al. formulated the theory and the experimental validation that allowed the awarding of the prize. It's a long time to wait to see if you were correct. Had the LHC gone off track, or if the Higgs happened to reside outside where it could look, he could have been long gone by the time we discovered it.

I wonder if that will become more common as theories predict things at energies that far exceed our current abilities.

The 6-sigma tells us the signal is there and it isn't noise, right? But are we sure now that it's the Higgs Boson? Could it still be another particle or some other phenomenon other than the Higgs? Honest question, I'd love to know and am an absolute layman in physics.

It's known to be a spin-0, positive parity particle which are both requirements for the Higgs. There have also been observations of specific predicted decay paths in approximately the right numbers.

I don't know the certainties on any of those things. But they all point towards this being an actual Higgs Boson. Certainly they can't do anything but rely on it having Higgs-like properties. If nature is fooling them, it's a good trick it's pulling.

Interactions between the Higgs field and particles help provide particles with mass, with particles that interact more strongly having larger masses.

As someone who understood that sentence, I just have to give you serious props for putting it together. It must have been hell.

On the topic of Nobel prizes only going to up to 3 people though, to everyone arguing about it now - do recognize that in deciding who these three people are, they aren't saying there aren't more people out there that did things key to its success - they're saying these people were the innovators; the ones that pushed forward with the first steps of imagination required to pull mankind to a higher level.

There's a Nobel for literature, peace, even economics - don't lose sight of how creative and rewarding science can be in its own right - not just in a material sense.

I feel sorry for the LHC team, but it's kind of understandable why the Nobel prize is awarded to individuals and not corporations and research centers. It's purpose is to motivate individuals and reward their excellence.

Peter Higgs sure had a long time to wait.

If it is supposed to motivate the researchers that the prize is awarded to, it doesn't make much sense to award the prize to someone who did research half a century ago- how many researchers are still active in the field after those many years?

If it is supposed to motivate other researchers- well the overwhelming majority of researchers will not end up getting the Nobel prize, so I am not sure how much of a motivation that is. I think researchers would be much more motivated if they could get more funding for their research now rather than a chance at a prize several decades later.

The 6-sigma tells us the signal is there and it isn't noise, right? But are we sure now that it's the Higgs Boson? Could it still be another particle or some other phenomenon other than the Higgs? Honest question, I'd love to know and am an absolute layman in physics.

It's known to be a spin-0, positive parity particle which are both requirements for the Higgs. There have also been observations of specific predicted decay paths in approximately the right numbers.

I don't know the certainties on any of those things. But they all point towards this being an actual Higgs Boson. Certainly they can't do anything but rely on it having Higgs-like properties. If nature is fooling them, it's a good trick it's pulling.

Very good. But this is why there's a lot of talk in (certain; neutrino physicists aren't really part of this conversation, for instance) particle physics circles about new experiments to do precision probes of the Higgs-like boson's properties and detect whether there are any other Higgs-like particles around (which certain theories predict), for example the International Linear Collider.

Could the discovery of Higgs boson render theoritical graviton obsolete ? I don't think so, but it could definitely mean the existence of more natural forces other the already known four.

Nope, the Higgs mechanism is orthogonal to the issue of quantum gravity. The Higgs really has nothing to do with gravity at all, excepting that the Higgs potential of particles is a form of energy and thus like all energy is a source of gravitation. If gravity is quantized, then the graviton is the unit of quantization and this should still be separate from the Higgs.

First, what exactly is the Higgs mechanism? I ask here because I know there are people who can explain it and I'm not familiar with Reddit (I've seen some great stuff there, but mostly linked from Dan Rutter on Twitter). I've read about scalar fields, but I'm not sure what that really means.

Second: on the Nobel prize being awarded to just three people. Whole institutions can and have received awards (IPCC, IAEA), though individual people in those organisations cannot claim to have received the prize themselves. To me though it would have seemed strange to award the Nobel to one of the CERN teams (and which organisation should have got it? Atlas? CMS?), and not award it to Higgs or Englert.

Maybe they'll change the rules for the future, though. Due recognition is important.

Him getting it this year should come at no surprise. The certainty associated with the data for the Higgs particle crossed the 5-sigma threshold last year. The Nobel Prize going to him now is if anything as immediate as it could get.

(btw, we're over 6-sigma certainty of the Higgs Boson now)

The 6-sigma tells us the signal is there and it isn't noise, right? But are we sure now that it's the Higgs Boson? Could it still be another particle or some other phenomenon other than the Higgs? Honest question, I'd love to know and am an absolute layman in physics.

The 6-sigma says that this is not a statistical fluke. (We've rolled so many double 6s in a row that we are now confident it's not just dumb luck.)

This particle is definitely a Higgs boson of some kind, meaning it is at least partly responsible for symmetry breaking and providing mass to many particles, most crucially the W and Z. It may or may not be the Standard Model Higgs boson, but that is irrelevant to the awarding of the prize to Higgs and Englert, since they developed the mechanism and general idea, which is now validated. It is the prediction of Steven Weinberg and the other formulators of the SM of the exact form that the boson would take that remains an open question. So far, the boson is consistent with the SM Higgs, but there's still room for deviation.

First, what exactly is the Higgs mechanism? I ask here because I know there are people who can explain it and I'm not familiar with Reddit (I've seen some great stuff there, but mostly linked from Dan Rutter on Twitter). I've read about scalar fields, but I'm not sure what that really means.

At a layman level: it is a way to get around a notorious theorem due to Jeffrey Goldstone (who probably should have gotten the third slot on this Prize, but it is likely left open as an homage to Brout) that caused huge problems for people trying to give the W and Z bosons mass, which they (and all other spin 1 = photon-like bosons) cannot have intrinsically without, for example, the probability of two W bosons bouncing off each other being greater than 1. We really, really don't believe in probabilities greater than 1.

Loosely speaking, the theorem states that, if a symmetry is broken spontaneously in a way that might give mass to spin 1 bosons, you must get a massless spin 0 boson as a result. This is a problem, because a massless spin 0 boson would have been detected long ago, so apparently there's no symmetry breaking, except the W and Z are massive, so there is definitely symmetry breaking. Higgs et al found an exception to the theorem, a way to dance around its assumptions that is still consistent with QFT, that makes the resulting boson massive, making it possible that with just a little more energy we could see it (insert pause of implication here).

Quote:

Second: on the Nobel prize being awarded to just three people. Whole institutions can and have received awards...

Only the Nobel Peace Prize (which is awarded by a different body entirely) has ever been given to organizations.

Very good. But this is why there's a lot of talk in (certain; neutrino physicists aren't really part of this conversation, for instance) particle physics circles about new experiments to do precision probes of the Higgs-like boson's properties and detect whether there are any other Higgs-like particles around (which certain theories predict), for example the International Linear Collider.

First of all, even through the statistics is very good (past 6 sigma, as some other posters mentioned), we're still very early on after the initial discovery. Making sure everything is OK, accumulating more data and refining the analysis will take time.

Then, data from independent sources, using other methods or probing other phenomena, is always good for the reliability of the discovery.

About the "other Higgs-like particles": there is good consensus on the fact that there can't be only one Higgs. If memory serves, a single Higgs leads to fine-tuning problems. It's been a while since I studied those, but most modern models rely on supersymmetry to describe a family of Higgs particles. It stands to reason that the one that was found last year is the lightest one. If another member of the family happened to have a larger mass, but not too much larger, we could hope to detect it in the near future. That would also help to discriminate models of Higgs families.

First, what exactly is the Higgs mechanism? I ask here because I know there are people who can explain it and I'm not familiar with Reddit (I've seen some great stuff there, but mostly linked from Dan Rutter on Twitter). I've read about scalar fields, but I'm not sure what that really means.

I'll go for a non-technical explanation. Feel free to ask again if you want more.

Back in the 60's, an apparent flaw was discovered in particle physics theory. The new theory that was gaining momemtum was suddenly discovered to be incompatible with particles having any mass. Several physicists from that time suggested a possible correction to the theory to save it and make it compatible with mass: the Higgs mechanism.

In fact, at least for a while, all that wasn't really necessary to make predictive computations in that theory. After all, a lot of great discoveries were made in the following decades without it. But as we approached the technological threshold where the Higgs could appear as a particle, it became urgent to make sure.

Be careful of the word "particle". Even when the Higgs doesn't manifest itself as a particle, it can still be there as a field, extending across the universe (a field not producing any particle is called a void, but it's anything but void!) As such, it serves as a medium inside which all particles propagate. As those particles interact with the Higgs field, their movement is impaired, which we perceive as mass (inertia, if you will).

Even though the Higgs field is everywhere, what was done last year is forcing that field to manifest a particle, and detect that particle. The Higgs void itself isn't detectable directly, we will only notice it through the fact that particles have mass.

I don’t see that it makes any point that someone in the Swedish academy just decides that this work is noble enough to receive a prize — I’ve already gotten the prize. The prize is the pleasure of finding a thing out, the kick in the discovery, the observation that other people use it — those are the real things. The honors are unreal to me. I don’t believe in honors.”

I don’t see that it makes any point that someone in the Swedish academy just decides that this work is noble enough to receive a prize — I’ve already gotten the prize. The prize is the pleasure of finding a thing out, the kick in the discovery, the observation that other people use it — those are the real things. The honors are unreal to me. I don’t believe in honors.”

Him getting it this year should come at no surprise. The certainty associated with the data for the Higgs particle crossed the 5-sigma threshold last year. The Nobel Prize going to him now is if anything as immediate as it could get.

(btw, we're over 6-sigma certainty of the Higgs Boson now)

The 6-sigma tells us the signal is there and it isn't noise, right? But are we sure now that it's the Higgs Boson? Could it still be another particle or some other phenomenon other than the Higgs? Honest question, I'd love to know and am an absolute layman in physics.

Second: on the Nobel prize being awarded to just three people. Whole institutions can and have received awards...

Only the Nobel Peace Prize (which is awarded by a different body entirely) has ever been given to organizations.

I was thinking the same thing. But the language of the will is the same for the different awards (IIRC), so the only reason to continue doing it this way (Peace Prize can include organizations, other prizes can't) is tradition.

Joiry wrote:Really shows why the Nobel Prize is anachronistic compared to how modern science works, in physics and other fields. Its a hugely collaborative process, and trying to single out a few individuals like some sort of pseudo-sports stars is not just inaccurate, but even harmful, imo.

Would you mind to elaborate what you mean by "harmful"?

Maybe you have a point there, but I sincerely to say that I disagree with you, even on the "harmful" part. I know nothing about science. <sighs> After all these readings on Ars I still couldn't figure out this quantum theory. What in the world are they talking about? But I do know one thing that a Nobel Prize makes a person proud of his work and proud of being a scientist.

From a non-scientist point of view, me, what make this Nobel Prize so proud for one to have is not only because it carries the name "Nobel" but It is because this "Prize" is not for everyone to have. This person must be on top of all super smart scientists around the world. Imagine what would other scientists think of the Nobel Prize when one goes to each one of the 3,000 science researchers at the LHC. It sure wouldn't make these three Prize winners a much proud person and an outstanding person at the science world. The Prize is for their 30 years hard work. Otherwise a free dinner for five at the local steak house comes more welcome. :-)